private static List <int> GetDiagonalIndicesForSquare(Square square, BoardData boardData)
        {
            List <Square> squares = BoardPositionUtility.DiagonalSquares(square.Data.Position, boardData);

            squares = ClearNullAndSelfSquares(squares, square);
            return(GatherIndicesForSquares(squares));
        }
        private static List <int> GetNeighborIndicesForSquare(Square square, BoardData boardData)
        {
            List <Square> squares = BoardPositionUtility.SurroundingSquares(square.Data.Position, boardData);

            // squares = ClearNullAndSelfSquares(squares, square);
            return(GatherIndicesForSquares(squares));
        }